To safely and thoroughly uninstall MySQL and clean all residual files, follow the following steps: 1. Stop MySQL service; 2. Uninstall MySQL packages; 3. Clean configuration files and data directories; 4. Verify that the uninstallation is thorough.

Oracle is not only a database company, but also a leader in cloud computing and ERP systems. 1. Oracle provides comprehensive solutions from database to cloud services and ERP systems. 2. OracleCloud challenges AWS and Azure, providing IaaS, PaaS and SaaS services. 3. Oracle's ERP systems such as E-BusinessSuite and FusionApplications help enterprises optimize operations.

MongoDB is suitable for handling large-scale unstructured data, and Oracle is suitable for enterprise-level applications that require transaction consistency. 1.MongoDB provides flexibility and high performance, suitable for processing user behavior data. 2. Oracle is known for its stability and powerful functions and is suitable for financial systems. 3.MongoDB uses document models, and Oracle uses relational models. 4.MongoDB is suitable for social media applications, while Oracle is suitable for enterprise-level applications.

Building a Hadoop Distributed File System (HDFS) on a CentOS system requires multiple steps. This article provides a brief configuration guide. 1. Prepare to install JDK in the early stage: Install JavaDevelopmentKit (JDK) on all nodes, and the version must be compatible with Hadoop. The installation package can be downloaded from the Oracle official website. Environment variable configuration: Edit /etc/profile file, set Java and Hadoop environment variables, so that the system can find the installation path of JDK and Hadoop. 2. Security configuration: SSH password-free login to generate SSH key: Use the ssh-keygen command on each node

MongoDB is suitable for unstructured data and high scalability requirements, while Oracle is suitable for scenarios that require strict data consistency. 1.MongoDB flexibly stores data in different structures, suitable for social media and the Internet of Things. 2. Oracle structured data model ensures data integrity and is suitable for financial transactions. 3.MongoDB scales horizontally through shards, and Oracle scales vertically through RAC. 4.MongoDB has low maintenance costs, while Oracle has high maintenance costs but is fully supported.

Configuring WebLogic database connection on a CentOS system requires the following steps: JDK installation and environment configuration: Make sure that the server has installed a JDK that is compatible with the WebLogic version (for example, WebLogic14.1.1 usually requires JDK8). Correctly set JAVA_HOME, CLASSPATH and PATH environment variables. WebLogic installation and decompression: Download the WebLogic installation package for CentOS system from the official Oracle website and unzip it to the specified directory. WebLogic user and directory creation: Create a dedicated WebLogic user account and set a security password

CentOS has been discontinued, alternatives include: 1. Rocky Linux (best compatibility); 2. AlmaLinux (compatible with CentOS); 3. Ubuntu Server (configuration required); 4. Red Hat Enterprise Linux (commercial version, paid license); 5. Oracle Linux (compatible with CentOS and RHEL). When migrating, considerations are: compatibility, availability, support, cost, and community support.

Running Kotlin in VS Code requires the following environment configuration: Java Development Kit (JDK) and Kotlin compiler Kotlin-related plugins (such as Kotlin Language and Kotlin Extension for VS Code) create Kotlin files and run code for testing to ensure successful environment configuration